It's a simple question I've asked you, but then key to your position is the avoidance of the same.
In your cut and paste description what do you understand by 'observations'?
If you understand observations to mean something like 'golly that okapi that landed in my lap is a funny colour and has a long neck', then you know perfectly well that you can hold on to your position as long as you like, as speciation does not happen like that in terms of interspecies transitions, interspecies differentiation (you want a new species to be grossly different, subtle changes are not enough) and typical time scales.
The above understanding of observations where;
- Ring species where interbreeding occurs at the ends of a ring is rare are not good enough as there is some gene flow.
- New species of (e.g.) fertile plant that are not fertile with the originating species of plant/s are not good enough, as the differences are too subtle for your definition even though there is no gene flow.
- Your refusal to accept the reasonable modern understanding of species (scientific species names are place markers of note, not the beginings of new chapters) or to 'join the dots' and see the implication of what we can observe over longer time scales.
... means you can maintain the pretence of having a reasonable position to your heart's content.
However, such a position does not preclude macroevolution from being a fact; it is a 'pyrrhic victory', if you like. You make yourself right by defintion, but actually miss how wrong you might be. Slight of hand, not impressive, not that you should try to impress anyone but are you actually kidding yourself?
If by observation one allows fossil evidence, extrapolation of events observable in human time-scales, genetic evidence, etc., then your refusal to see the slow gradual change between grossly different forms is not really tenable.
So, am I right about you having a 'in front of my eyes' (or something close to it) defintion of observable?
Now, back to the bits you are ignoring as you can't answer them to any level of satisfaction and keep your ID hypothesis credible.
- ID requires the designer to pop up at various points since life began to introduce new species. Thus it is required to be explained IN the hypothesis. Go on then.
- Atavisms such as dolphin limbs and human tails are not explicable as 'inbuilt design variation'. Humans have no conceivable use for tails; if they do, please let me in on your insight. Likewise, non-functional limbs are a useless design variation to cope with environmental stress for dolphins, and a decent designer could make 'inbuilt design variation' produce usable features within one generation.
- Genetic evidence points to lines of descent due to the unique 'finger print' of an endoviral infection event being inexplicable by other means; you can't credibly say 'oh, each species caught the endovirus independently' as the genetic evidence of this would be different from that we find in (e.g.) chimps and humans.
- Why do you limit the power of the designer? You seem to believe that a designer of the ilk you speculate is limited to producing a range of 'cars' that can modify themselves to suit 'market forces', but will always remain a Ford Taurus/Dodge Viper etc., and never become a bus, a tractor-trailer, etc. Why can the designer not have the design savvey to set up the very rules so the OUTPUT of the system is what it wanted based upon an initial single design event?